Are investors really willing to agree to disagree? An experimental investigation of how disagreement and attention to disagreement affect trading behavior

Using a series of laboratory markets, this paper provides evidence that a willingness to engage in speculative trade is largely driven by a failure of traders to account for information about value implicit in other traders’ actions and that this behavior arises because traders construct myopic mental models that ignore the perspective of other traders. In a baseline set of markets, where traders are prompted to estimate fundamental value but are not overtly prompted to consider disagreement, I find that traders are generally insensitive to adverse selection and readily engage in suboptimal, speculative trade. Moreover, this effect does not decline across trials suggesting that market feedback alone is unlikely to correct traders’ behavior. In contrast, when traders are prompted to assess disagreement over asset values or when they trade in more transparent markets, they appear less willing to “agree to disagree.” These results provide insight into why investors depart from rational trading strategies and how investor psychology will influence trading behavior.     

What 50 years of research tell us about pausing under ratio schedules of reinforcement

Textbooks in learning and behavior commonly describe performance on fixed-ratio schedules as “break and run,” indicating that after reinforcement subjects typically pause and then respond quickly to the next reinforcement. Performance on variable-ratio schedules, on the other hand, is described as steady and fast, with few long pauses. Beginning with Ferster and Skinner''s magnum opus, Schedules of Reinforcement (1957), the literature on pausing under ratio schedules has identified the influences on pausing of numerous important variables, in particular ratio size and reinforcement magnitude. As a result, some previously held assumptions have been called into question. For example, research has shown that the length of the pause is controlled not only by the preceding ratio, as Ferster and Skinner and others had assumed (and as implied by the phrase postreinforcement pause), but by the upcoming ratio as well. Similarly, despite the commonly held belief that ratio pausing is unique to the fixed-ratio schedule, there is evidence that pausing also occurs under variable-ratio schedules. If such widely held beliefs are incorrect, then what about other assumptions? This article selectively examines the literature on pausing under ratio schedules over the past 50 years and concludes that although there may indeed be some common patterns, there are also inconsistencies that await future resolution. Several accounts of pausing under ratio schedules are discussed along with the implications of the literature for human performances, most notably the behaviors termed procrastination.     

Serotonin transporter 5-HTTLPR genotype is associated with intrusion and avoidance symptoms of DSM-5 posttraumatic stress disorder (PTSD) in Chinese earthquake survivors

Background and Objectives: Prior studies have found that the serotonin transporter gene-linked polymorphic region (5-HTTLPR) interacts with trauma exposure to increase general risk for Posttraumatic Stress Disorder (PTSD). However, there is little knowledge about the effects of the interaction on distinct symptom clusters of PTSD. This study aimed to investigate the relation between the interaction of 5-HTTLPR and earthquake-related exposures and a contemporary phenotypic model of DSM-5 PTSD symptoms in a traumatised adult sample from China.

Design: A cross-sectional design with gene-environment interaction (G?×?E) approach was adopted. Methods: Participants were 1131 survivors who experienced 2008 Wenchuan earthquake. PTSD symptoms were assessed with the PTSD Checklist for DSM-5 (PCL-5). The 5-HTTLPR polymorphism was genotyped with capillary electrophoresis (CE) in ABI 3730xl genetic Analyzer.

Results: Although there was no significant interaction between 5-HTTLPR and traumatic exposure on total PTSD symptoms, respondents with the LL genotype of 5-HTTLPR who were highly exposed to the earthquake experienced lower intrusion and avoidance symptoms than those with the S-allele carriers.

Conclusions: The findings suggest that the 5-HTTLPR may have an important impact on the development of PTSD and add to the extant knowledge on understanding and treating of posttraumatic psychopathology.     

传媒介入医患纠纷的原因及作用探析

探讨传媒介入医患纠纷的原因及作用。经过分析发现,竞争的需要、经济的需要和受众的需要是传媒介入医患纠纷的主要动机和原因。总体而言,对传媒介入医患纠纷应持肯定态度。它在将医患矛盾进行公开化,唤起公众对医患纠纷问题的重视,提升公众参与意识,以及促进解决结果的公平性与公正性等方面发挥了积极作用。     

Normative Developmental Trajectories of Aggressive Behaviors in African American,American Indian,Asian American,Caucasian, and Hispanic Children and Early Adolescents

The current 5-year accelerated longitudinal investigation modeled the developmental trajectories of aggressive behaviors in 10,107 predominantly minority (>70%; African American, American Indian, Asian American, and Hispanic) children and early adolescents (Kindergarten through 8th grade, 49% female youth) from lower to lower-middle socioeconomic strata. Based on a two-part latent growth model, findings suggest that the probability and frequency of aggressive behavior use decreases slightly (linear) through the elementary school years and then increases as children move into middle school (quadratic). Though mean level differences were found across ethnic and racial groups, socioeconomic strata, and particularly by sex at initial status, rates of change over time across all groups were invariant. Findings suggest that potential socialization differences, if any, occur pre-Kindergarten in all groups.     

Understanding memory impairment with memory models and hierarchical Bayesian analysis

The study of human episodic memory is a topic that interests cognitive and mathematical psychologists as well as clinicians interested in the diagnosis and assessment of Alzheimer’s disease and related disorders (ADRD). In this paper, we use simple cognitive models for the recognition and recall tasks typically applied in clinical assessments of ADRD to study memory performance in ADRD patients. Our models make use of hierarchical Bayesian methods as a way to model individual differences in patient performance and to facilitate the modeling of performance changes that occur during multiple recall tasks. We show how the models are able to account for different aspects of patient performance, and also discuss some of the predictive capabilities of the model. We conclude with a discussion on the scope to improve on our results by discussing the link between memory theory in psychology and clinical practice.     

Sex differences in latent cognitive abilities ages 5 to 17: Evidence from the Differential Ability Scales—Second Edition

Sex differences in the latent general and broad cognitive abilities underlying the Differential Ability Scales, Second Edition were investigated for children and youth ages 5 through 17. Multi-group mean and covariance structural equation modeling was used to investigate sex differences in latent cognitive abilities as well as changes in these differences across age. Most broad abilities showed mean differences across the sexes, and all such differences varied across ages. Girls showed an advantage on the processing speed (Gs) first-order residual factor. Girls also showed advantages at some ages on free-recall memory, a narrow ability of long term retrieval (Glr). Boys showed a developmentally-related advantage on a visual-spatial ability (Gv) first-order residual factor, depending on age. Younger girls showed an advantage on short-term memory (Gsm). No statistically significant sex differences were shown on the latent comprehension-knowledge (Gc) factor, or on a second-order, latent g factor. Boys showed larger variances for several broad abilities, some substantial, but those differences were not statistically significant.     

Transfer effects between moral dilemmas: A causal model theory

Evaluations of analogous situations are an important source for our moral intuitions. A puzzling recent set of findings in experiments exploring transfer effects between intuitions about moral dilemmas has demonstrated a striking asymmetry. Transfer often occurred with a specific ordering of moral dilemmas, but not when the sequence was reversed. In this article we present a new theory of transfer between moral intuitions that focuses on two components of moral dilemmas, namely their causal structure and their default evaluations. According to this theory, transfer effects are expected when the causal models underlying the considered dilemmas allow for a mapping of the highlighted aspect of the first scenario onto the causal structure of the second dilemma, and when the default evaluations of the two dilemmas substantially differ. The theory’s key predictions for the occurrence and the direction of transfer effects between two moral dilemmas are tested in five experiments with various variants of moral dilemmas from different domains. A sixth experiment tests the predictions of the theory for how the target action in the moral dilemmas is represented.     

Theory and teen dating violence victimization: Considering adolescent development

Teen dating violence is an important public health problem, with implications for the future health and well-being of adolescents. However, most work on teen dating violence has developed separately from literature on normative adolescent romantic relationships and development; understanding teen dating violence within the framework of adolescent psychosocial development may provide new areas for research. Thus, the present paper summarizes five theories of adolescent development that are relevant to the study of teen dating violence victimization, as well as empirical literature that demonstrates support for key theoretical tenets in research examining adolescent romantic relationships. We also present questions for future dating violence study that arise from these key theoretical tenets and past empirical research. Researchers interested in dating violence victimization can use the presented theories to guide new directions in research inquiry, so that findings are situated within the broader field of adolescent development.     

Public concerns about violent video games are moral concerns—How moral threat can make pacifists susceptible to scientific and political claims against violent video games

Public discussions about the harmfulness of violent media are often held in the aftermath of violent felony. At the same time, we know little about whether and how experiencing real‐life violence impacts the way laypersons perceive and evaluate debates about virtual violence. In Study 1, we provided data indicating that both real‐life violence and violent video games are perceived as morally threatening by people who regard nonviolence to be an important moral value (i.e., pacifists). In Study 2, we hypothesized and found that when pacifists perceive threat from the presence of real‐life violence, they are especially susceptible to scientific and political claims indicating that violent video games are harmful. Our findings are in line with the value protection model and research on the psychological consequences of threat. Implications of the present findings are discussed with regard to a better understanding of the violent video games debate in the general public.